Fix #warn -> #warning

Although it never happens, lets fix this.

Signed-off-by: Pantelis Antoniou <pantelis.antoniou@konsulko.com>

src/lib/fy-parse.c

@@ -37,7 +37,7 @@
 const char *fy_library_version(void)
 {
 #ifndef VERSION
-#warn No version defined
+#warning No version defined
 	return "UNKNOWN";
 #else
 	return VERSION;